SF: Add new fields to transactions proto

- track layer handle removal so layer lifecycle
  can be recreated accurately when rebuilding layer
  state
- track buffer format since it affects opacity
- track transaction ids to track transactions
  across the system
- also fixes relative z tracking

Test: atest TransactionProtoParserTest
Bug: 200284593
Change-Id: I037e40219f9fee8957051352beeba88681b8cf43
diff --git a/services/surfaceflinger/BufferLayer.h b/services/surfaceflinger/BufferLayer.h
index 34d11ac..99267be 100644
--- a/services/surfaceflinger/BufferLayer.h
+++ b/services/surfaceflinger/BufferLayer.h
@@ -111,6 +111,7 @@
     ui::Dataspace getDataSpace() const override;
 
     sp<GraphicBuffer> getBuffer() const override;
+    const std::shared_ptr<renderengine::ExternalTexture>& getExternalTexture() const override;
 
     ui::Transform::RotationFlags getTransformHint() const override { return mTransformHint; }